Nusra Front fighter in Syria
Nusra Front fighter in SyriaReuters

Syrian insurgents, including fighters from the Al-Qaeda affiliate Al-Nusra Front, seized a key city and other areas of Syria's southwestern Deraa province on Sunday after five days of fierce battles, fighters in the area told Reuters.

A source close to government forces confirmed the advance and said the army had pulled out of Nawa city.

The capture of Nawa and surrounding areas will help the insurgents consolidate control of territory stretching to near the Golan Heights.

"Some of the (government) soldiers escaped at night, the rest escaped today," one insurgent told Reuters. "They left their heavy weapons and their military vehicles behind."

The insurgents also seized the surrounding areas of Sheikh al-Maskin, Tal Hauran and a military headquarters known as the 122 Brigade in the major offensive, the sources said.

Some of the fighting in Syria has already several times spilled over into Israel. The most recent incident was in early October, when an explosion was heard close to an IDF post near the Syrian border in the Golan Heights, causing no injury or damage.

That explosion occurred days after Israel shot down a rogue Syrian Army fighter jet near the Golan Heights with a patriot missile - and after it shot down a Syrian drone after it strayed into Israeli airspace in August.

Al-Nusra Front, whose leader pledged allegiance to Al-Qaeda, has been heavily involved in the fighting in Syria as well as in neighboring Lebanon, where it has claimed responsibility for several bombings and has also threatened local Sunnis.

The head of the group has threatened attacks against the Shiite Hezbollah in Lebanon, due to its involvement in the Syrian civil war, fighting alongside government troops.